Episode 13 of Kamisama no Inai Nichiyoubi, included in the final Blu-ray/DVD volume of the series. This bonus episode is separated into three parts. In the first part, taking place before the characters reach Ostia, Ai and the others visit a hot spring. In the second part, Alice remembers the times he killed his classmates and encounters Hampnie Hambart. A battle ensues. In the third and final part, Hampnie dreams of when he first met Hana and is then woken up by Ai. (Source: Wikipedia)

The OVA was scheduled for January 2014, but was delayed to February and was included on the fifth Blu-ray of the anime release.